Network, cable television, and satellite television providers often have Video on Demand (VOD) systems that allow users to select, watch, and listen to video or audio content on demand. Typically, a user buys or selects a movie or television program and the content is almost immediately streamed to a set-top box. Some VOD systems deliver VOD content using the Internet protocol (IP). The set-top box then begins to play the content on a television coupled to the set-top box. Often, while watching, the user can pause, rewind, fast forward, or reposition playback of the content. The service provider alters the content stream to accommodate the user's pausing, rewinding, fast forwarding, or repositioning.
The VOD content is often encrypted by the provider before it is transmitted to the set-top box. The set-top box receives the encrypted content and decrypts the content. Then, the set-top box may provide the content to the television in yet another encrypted format.